389 



and contains altogethor 80,000 sheets. It is valuable, on account of 

 its being chiefly composed of exotic specimens, including plants col- 

 lected by Sieber, Preiss, Wallich, Wight, Ecklon, Zeyher, Drege, 

 Poppe, Wied, and others, and representing most fully the floras of 

 New Holland, Southern Africa, Mexico, the East Indies, and Europe. 

 What renders it still more important is its containing the original 

 specimens on which M. von Esenbeck's monographic labours, his dis- 

 sertations on the Laurineae, Solaneae, Acanthaceae, Hepaticse, Asterese, 

 Cyperacege, Gramineae, and Restiaceae, are founded. 



The library is composed of 3002 volumes, embracing the standard 

 works of natural history and natural philosophy. It is to be sold in 

 Breslau, on the 1st of May, 1852, by public auction, and commissions 

 will be received by the " Schlettersche Buchhandlung" in Breslau, or 

 by any other great bookseller on the Continent. The herbarium, if it 

 cannot be sold as a whole, is to be disposed of in sets. It has been 

 valued at 12,000 thalers, but there can be no doubt that it will fetch a 

 much higher price. The Laurineae are valued at 280 thalers, the 

 Acanthaceae at 600, and the Glumaceae at 3000. 



It is to be hoped that these treasures will not be dispersed, but that 

 some institution or private individual, ready to make them available 

 to the scientific public, will become the purchaser, that, after party 

 squabbles have been forgotten, posterity may behold the entire col- 

 lections of a man whom the present age justly considers one of the 

 most eminent of which science can boast. 



P. V. P. 



Microscopical Society of London. 



October 22, 1851.— A paper was read by Geo. Shadbolt, Esq., *0n 

 the Sporangia of some of the Filamentous Freshwater Algae.' 



This was in continuation of a subject introduced to the notice of the 

 Society in May last, by the same gentleman, when he pointed out the 

 fact, that in Zygnema quadratum and Z. varians the sporangia un- 

 dergo a considerable change of form, assuming a stellate character 

 after the lapse of some weeks from their first formation. The second 

 paper detailed observations confirming those previously announced, 

 and giving some of the particulars of the modus operandi, and added 

 Lyngbya floccosa and a species of Vesiculifera to the list of those in 

 which the author had noted an analogous transformation. It was 

 stated that in Zygnema varians, after conjugation, when the sporan- 



